Increasing medical problems have been identified among people using keyboards because of muscle fatigue, Carpal Tunnel Syndrome, shoulder strain, neck and back strain, and other repetitive motion disorders. Observation of users of keyboards has indicated that much of the underlying stress is back-related, not just wrist related. The very nature of the finger/hand/wrist/arm movements creates stress and tension on the shoulders, necks, and arms of keyboard users. Joan Duncan and D. Ferguson published a study of keyboard operations and the effect on the human body in Ergonomics, 1974, emphasizing the need to concentrate on back and neck muscle groups. Fitting the Task to the Man notes that the elbows must be close-in to the body and straight with the shoulders. "Lifting the shoulders is strenuous . . . work," according to the author's research. A Swiss ergonomics study in 1982 pointed out that 83% of keyboarders rested their forearms if a devise to do so was available which supports other research which indicate that shoulder and neck muscles suffer during the workday. Various studies have concentrated on methods to relieve the wrist tensions and numerous hard surface and soft surface inventions have been created and marketed to relieve tension and pressure on wrists and forearms. Most have been static devises attached to the keyboard or desktop rather than attached to the keyboard operator.